Several important players are missing from this critical event: Ding Liren above all, as well as Dmitry Andreikin and Kirill Alekseenko. That's three former Candidates, including the world's #3 player. I don't know what the organizers can do, though; maybe they have no perfect way to deal with the bad hand dealt by COVID.
At any rate, the tournament is proceeding with the players they could get. The Grand Prix is a series of three tournaments, with each player participating in two events - at least that's how it's supposed to go. This is the first event, in Berlin. There are 16 players divided into four groups. Each group will contest a double round robin, and the winner of each group will meet in a knockout final. Here are the groups, and the results of Friday's games:
Group 1: Alexander Grischuk, Hikaru Nakamura (playing his first classical event in more than two years), Andrey Esipenko, and Etienne Bacrot.
Round 1: Esipenko-Grischuk and Bacrot-Nakamura both finished in draws.
Group 2: Levon Aronian, Daniil Dubov, Vincent Keymer, and Santosh Gujrathi Vidit
Round 1: Aronian-Vidit 1-0, Keymer-Dubov was drawn.
Group 3: Vladimir Fedoseev, Radoslaw Wojtaszek, Richard Rapport, and Grigoriy Oparin
Round 1: Fedoseev-Oparin and Wojtaszek-Rapport were both 1-0.
Group 4: Wesley So, Leinier Dominguez, Pentala Harikrishna, and Alexei Shirov
Round 1: So-Dominguez and Shirov-Harikrishna were both drawn.
The event website, with an absolutely bizarre front page, is here.