[5] Lys Gracieux began her racing career by finishing second to the colt Root Directory in a contest for previously unraced juveniles over 1600 metres at Niigata Racecourse on 27 August.

After racing towards the rear of the eighteen-runner field she produced a strong late charge but was unable to reel in the favourite Soul Stirring and finished second, beaten one and a quarter lengths by the winner.

In the Grade 1 Oka Sho over the same course and distance five weeks later she produced a sustained challenge in the straight and finished second, beaten half a length by the 40/1 outsider Reine Minoru with Soul Stirring in third place.

In the Grade 1 Shuka Sho a month later the filly produced her customary late charge, caught the leader Mozu Katchan 50 metres from the finish but was overtaken by the fast-finishing Deirdre in the final strides.

[11] On her final run of the year Lys Gracieux came home eighth behind Mozu Katchan in the Queen Elizabeth II Cup at Kyoto Racecourse on 12 November.

Lys Gracieux began her third campaign in the Grade 3 Tokyo Shimbun Hai over 1600 metres on 4 February in which she started the 4.5/1 third choice in the betting behind Daiwa Cagney and Greater London.

Ridden by Take she recorded her first win in sixteen months as she won by a length from the four-year-old colt Satono Ares (Asahi Hai Futurity Stakes).

[12] In April she started favourite for the Grade 2 Hanshin Himba Stakes but in a closely contested finish she ran third place, beaten a head and a neck by Miss Panthere and Red Avancer.

In the Yasuda Kinen over the same course and distance on 3 June she made little impact and came home eighth of the sixteen runners behind Mozu Ascot, beaten five and a half lengths by the winner.

[15] On her first run as a five-year-old in the Grade 2 Kinko Sho over 2000 metres at Chukyo Racecourse on 10 March she started at odds of 7.7/1 in a thirteen-runner field and finished second to the four-year-old colt Danon Premium.

She was partnered by Damian Lane and went off the 4.4/1 third choice in the betting behind Kiseki (2017 Kikuka Sho) and Rey de Oro, while the other contenders included Al Ain, Suave Richard and Makahiki.

After racing in second place behind the front-running Kiseki, Lys Gracieux challenged the favourite in the straight, gained the advantage 200 metres from the finish and drew away in the closing stages to win by three lengths.

She was given a special exemption to compete[17] as horses who had raced in Hong Kong were banned from entering Australia unless they had spent at least 180 days in a third country in the interim, after the Australian Government raised concerns over China's biosecurity regulations.

Ridden by Lane she went off the 5.7/1 second favourite behind Almond Eye in a sixteen-runner field which also included Saturnalia, World Premiere, Suave Richard, Fierement, Kiseki, Rey de Oro, Cheval Grand and Al Ain.