Shortly before the disappearance, Küblböck stated he wanted to assume a female identity and began using the name Lana Kaiser.

[3] Küblböck rose to stardom in late 2002 when he participated in the first season of German talent show Deutschland sucht den Superstar (DSDS).

Küblböck invested the proceeds from his album Positive Energie amounting to around one million euros in a solar plant in Lower Bavaria, which would bring him high monthly profits.

[6] In early 2004, he participated in Ich bin ein Star – Holt mich hier raus!, the German version of I'm a Celebrity...Get Me Out of Here!, where he came third.

[7] In August, Küblböck's biographical musical film Daniel – Der Zauberer was released, in which he played a fictionalized version of himself.

At the end of 2004, he released the charity single "Don't Close Your Eyes" with three others DSDS participants under the moniker 4 United, in support of Ärzte ohne Grenzen (Doctors Without Borders).

In 2012, he released the album Diez años Kúblbóck – Ich versteh’ nur Spanisch which included some material recorded in Spanish and influenced by Latin pop.

[21] Küblböck was a private passenger on the cruise ship AIDAluna that left Hamburg on 29 August 2018, bound for New York City.

[25] The Canadian Coast Guard launched a search operation,[26][27] assisted by the cruise ships AIDAluna and MS Zuiderdam.

[29] Under German law, a person missing at sea can be declared dead after six months have elapsed and a motion is filed by an eligible party.

On 10 March 2021, the Amtsgericht (district court) Passau declared Küblböck dead, setting his death date as 9 September 2018, 8:55 a.m. local time.

[31] In the weeks leading up to the disappearance, Küblböck's friends noticed changes in his personality and signs of psychological problems, unsuccessfully trying to dissuade him from going on the cruise.