Grey's Anatomy returns Thursday, March 24.

In "This Is How We Do It," Richard grows desperate for Derek and Meredith to accept Adele into their Alzheimer's trial, but it's Adele herself who may stand in their way.

Speaking of trials, competitiveness amongst the residents for the Chief Resident position is amplified when Richard receives the green light for his diabetes clinical trial.

Meanwhile, Teddy is alarmed when Henry has another health issue that "leaves them both a little exposed." What do you think that cryptic tease means? Any theories?

Finally, Mark and Arizona have conflicting ideas of what Callie's baby shower should entail. Much of the photo gallery below previews that event. Click to enlarge ...

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