In 1980, Waschke's father was hired as head of surgery at a hospital in Sulzbach, Saarland, and the family moved to Friedrichsthal.

[2] From 1999 until 2008, Waschke was a regular staff member of the Berlin Schaubühne theatre company under Thomas Ostermeier, who has described him as "a good-looking, virile actor who takes full responsibility for his play and display of emotional diversity".

[4] Since 2005, Waschke has appeared in television series and films, notably Buddenbrooks (2008), Habermann (2010), The City Below (2011), and Generation War (2013).

Since 2009, he has made regular appearances in the long-running crime drama series Tatort,[5] and in 2015, he gained a permanent role, playing detective Robert Karow.

[4] He has said that acting on stage is a mental and physical need, not only because it does not get interrupted as in filming but also "for a different kind of responsibility, for oneself, the role, the play, the great ritual, which at best doesn't only do something for the audience [...].